Application and prospect of semiconductor biosensors in detection of viral zoonoses

The rapid spread of viral zoonoses can cause severe consequences,including huge economic loss,public health problems or even global crisis of society.Clinical detection technology plays a very important role in the prevention and control of such zoonoses.The rapid and accurate detection of the pathogens of the diseases can directly lead to the early report and early successful control of the diseases.With the advantages of being easy to use,fast,portable,multiplexing and cost-effective,semiconductor biosensors are kinds of detection devices that play an important role in preventing epidemics,and thus have become one of the research hotspots.Here,we summarized the advances of semiconductor biosensors in viral zoonoses detection.By discussing the major principles and applications of each method for different pathogens,this review proposed the directions of designing semiconductor biosensors for clinical application and put forward perspectives in diagnostic of viral zoonoses.

South Asian dairy smallholders: A scoping review of practices and zoonoses

Objective: To identify and discuss on-farm management practices linked to bacterial zoonosis risk in smallholder dairy farmers in South Asia. Methods: This scoping review was conducted as per the PRISMA-ScR guidelines. Five hundred and two publications were retrieved from five online databases using a comprehensive search strategy. Studies were selected if they discussed a farm management practice which impacted human health within a South Asian country. Results: Twenty-two studies were included. Seven management practices relevant to farmers, livestock and their shared environment were identified including raw milk consumption, farm hygiene management, personal protective equipment uses, animal vaccination, cleaning udders, hand washing and disposal of afterbirth materials. Preventive practices were found to be utilized at lower frequencies compared to risk increasing practices. Awareness of bacterial zoonoses is particularly low within the region. Conclusions: Based on the results of this review, it was determined that improving farmer awareness of bacterial zoonotic diseases may favor several of the presented leverage points within the South Asian smallholder dairy system. Relying on formal school education to improve this awareness may not solve this problem, instead, more focus on accessible and affordable zoonoses education and farming programs is required.

Emerging and neglected zoonoses in transplant population

Zoonoses represent a problem of rising importance in the transplant population.A close relationship and changes between human,animal and environmental health(“One Health”concept)significantly influence the transmission and distribution of zoonotic diseases.The aim of this manuscript is to perform a narrative review of the published literature on emerging and neglected zoonoses in the transplant population.Many reports on donor-derived or naturally acquired(re-)emerging arboviral infections such as dengue,chikungunya,West Nile,tick-borne encephalitis and Zika virus infection have demonstrated atypical or more complicated clinical course in immunocompromised hosts.Hepatitis E virus has emerged as a serious problem after solid organ transplantation(SOT),leading to diverse extrahepatic manifestations and chronic hepatitis with unfavorable outcomes.Some neglected pathogens such as lymphocytic choriomeningitis virus can cause severe infection with multi-organ failure and high mortality.In addition,ehrlichiosis may be more severe with higher casefatality rates in SOT recipients.Some unusual or severe presentations of borreliosis,anaplasmosis and rickettsioses were also reported among transplant patients.Moreover,toxoplasmosis as infectious complication is a well-recognized zoonosis in this population.Although rabies transmission through SOT transplantation has rarely been reported,it has become a notable problem in some countries.Since the spreading trends of zoonoses are likely to continue,the awareness,recognition and treatment of zoonotic infections among transplant professionals should be imperative.

Prevalence of Giardia duodenalis among dogs seized by the Center for Control of Zoonoses (CCZ) of the city of Lages, Santa Catarina, Brazil

The knowledge of the epidemiology of parasitic infections in stray and domestic animals, especially of its incidence and prevalence, is fundamental to adopting effective prophylactic measures. Stray dogs play an important role in environmental contamination favoring the transmission cycle of zoonotic agents. Among the parasitic infections that affect humans, Giardia duodenalis is the most common intestinal protozoa and was designated as a re-emerging infectious disease. This study aimed to determine the prevalence of G. duodenalis in dogs siezed by the Center for Control of Zoonoses (CCZ) of the city of Lages, Santa Catarina, Brazil using two diagnostic techniques. In 357 stool samples analysed, the prevalence of G. duodenalis cysts was 5.3% (19/357) and 4.8% (17/357) detected by floatation and sedimentation techniques, respecttively. No correspondence between gender and age was found among the methods used for analyzing the infected dogs in this study. Our data suggested that two diagnostic techniques should be used in a complementary way to ensure that false negatives are not neglected.

Priorities for research and control of cestode zoonoses in Asia

Globally,cestode zoonoses cause serious public health problems,particularly in Asia.Among all neglected zoonotic diseases,cestode zoonoses account for over 75%of global disability adjusted life years(DALYs)lost.An international symposium on cestode zoonoses research and control was held in Shanghai,China between 28th and 30th October 2012 in order to establish joint efforts to study and research effective approaches to control these zoonoses.It brought together 96 scientists from the Asian region and beyond to exchange ideas,report on progress,make a gap analysis,and distill prioritizing settings with a focus on the Asian region.Key objectives of this international symposium were to agree on solutions to accelerate progress towards decreasing transmission,and human mortality and morbidity caused by the three major cestode zoonoses(cystic echinococcosis,alveolar echinococcosis,and cysticercosis);to critically assess the potential to control these diseases;to establish a research and validation agenda on existing and new approaches;and to report on novel tools for the study and control of cestode zoonoses.

Assessment of performance for a key indicator of One Health:evidence based on One Health index for zoonoses in Sub-Saharan Africa

Background:Zoonoses are public health threats that cause severe damage worldwide.Zoonoses constitute a key indicator of One Health(OH)and the OH approach is being applied for zoonosis control programmes of zoonotic diseases.In a very recent study,we developed an evaluation system for OH performance through the global OH index(GOHI).This study applied the GOHI to evaluate OH performance for zoonoses in sub-Saharan Africa.Methods:The framework for the OH index on zoonoses(OHIZ)was constructed including five indicators,15 subindicators and 28 datasets.Publicly available data were referenced to generate the OHIZ database which included both qualitative and quantitative indicators for all sub-Sahara African countries(n=48).The GOHI algorithm was used to estimate scores for OHIZ.Indicator weights were calculated by adopting the fuzzy analytical hierarchy process.Results:Overall,five indicators associated with weights were generated as follows:source of infection(23.70%),route of transmission(25.31%),targeted population(19.09%),capacity building(16.77%),and outcomes/case studies(15.13%).Following the indicators,a total of 37 sub-Sahara African countries aligned with OHIZ validation,while 11 territories were excluded for unfit or missing data.The OHIZ average score of sub-Saharan Africa was estimated at 53.67/100.The highest score was 71.99 from South Africa,while the lowest score was 40.51 from Benin.It is also worth mentioning that Sub-Sahara African countries had high performance in many subindicators associated with zoonoses,e.g.,surveillance and response,vector and reservoir interventions,and natural protected areas,which suggests that this region had a certain capacity in control and prevention or responses to zoonotic events.Conclusions:This study reveals that it is possible to perform OH evaluation for zoonoses in sub-Saharan Africa by OHIZ.Findings from this study provide preliminary research information in advancing knowledge of the evidenced risks to strengthen strategies for effective control of zoonoses and to support the prevention of zoonotic events.

Understanding and managing sanitary risks due to rodent zoonoses in an African city: beyond the Boston Model

The Boston Model describes a successful rodent management plan that succeeded in a first-world city in the USA.In third-world cities, which often contain informal shack settlements, it is debatable whether the Boston Modelwould apply. In Durban, a major harbor city of three million people on the east coast of South Africa, we investigatedthe sanitary risks due to rodents in both formal (residential and commercial) and informal (shacks) sectors,and we evaluated the relative merits of different management interventions suggested by the Boston Model. Bloodand tissue samples of six species (Rattus norvegicus, R. tanezumi, R. rattus, Mus musculus, Mastomys natalensis,Tatera brantsi) from 262 live-trapped rodents from 54 localities were tested for antibodies or DNA for plague (n =193: antibody test), leptospirosis (n = 221 for antibody test;n = 69 for polymerase chain reaction test for DNA) andtoxoplasmosis (n = 217: antibody test). We conducted a socioeconomic survey of 90 household to determine environmentaland socioeconomic disease risk factors in the shack settlement of Cato Crest . No rodents wereseropositive for plague, but nine Norway rats, R. norvegicus (4.1% of the sample tested) were seropositive fortoxoplasmosis, and 22 R. norvegicus (10.0% of sample tested) were seropositive for leptospirosis. Disease endemicareas were concentrated in Cato Crest and the commercial district of Durban. Serology tests of humans living inCato Crest (n = 219) showed 0% exposure to plague, 23% to leptospirosis and 35% to toxoplasmosis. Comparedwith shack-dwellers, the residents of brick houses had slightly lower levels of exposure to leptospirosis andtoxoplasmosis. Based on our results, environmental hygiene and rodent-trapping campaigns were launched in CatoCrest. The initiative owes much of its current success to implementation of the principles inherent in the BostonModel, even though certain elements were lacking.

Cultural drivers and health-seeking behaviours that impact on the transmission of pig-associated zoonoses in Lao People’s Democratic Republic

Pig rearing is an important income source in the Lao People’s Democratic Republic(PDR),with many smallholder farmers using traditional free-range pig production systems.Despite the potentially significant health risks posed by pig production regarding pig-associated zoonoses,information on the sociocultural drivers of these zoonoses is significantly lacking.This review summarises the existing sociocultural knowledge on eight pig-associated zoonoses suspected to be endemic in Southeast Asia:brucellosis,Q fever(Coxiella burnetii),trichinellosis,hepatitis E virus,leptospirosis,Japanese encephalitis,Streptococcus suis and Taenia solium taeniasis-cysticercosis.It summarises current knowledge on these diseases grouped according to their clinical manifestations in humans to highlight the propensity for underreporting.A literature search was conducted across multiple databases for publications from 1990 to the present day related to the eight pig-associated zoonoses and the risk and impact connected with them,with Lao PDR as a case study.Many of these pig-associated zoonoses have similar presentations and are often diagnosed as clinical syndromes.Misdiagnosis and underreporting are,therefore,substantial and emphasise the need for more robust diagnostics and appropriate surveillance systems.While some reports exist in other countries in the region,information is significantly lacking in Lao PDR with existing information coming mainly from the capital,Vientiane.The disease burden imposed by these zoonoses is not only characterised by morbidity and mortality,but directly impacts on livelihoods through income reduction and production losses,and indirectly through treatment costs and lost work opportunities.Other factors crucial to understanding and controlling these diseases are the influence of ethnicity and culture on food-consumption practices,pig rearing and slaughter practices,hygiene and sanitation,health-seeking behaviours and,therefore,risk factors for disease transmission.Published information on the knowledge,attitudes and beliefs of people regarding pig zoonoses and their risk factors is also extremely limited in Lao PDR and the broader Southeast Asian region.The need for more transdisciplinary research,using a One Health approach,in order to understand the underlining social determinants of health and their impacts on health-seeking behaviours,disease transmission and,ultimately,disease reporting,cannot be more emphasized.

Preliminary investigation on rodent–ectoparasite associations in the highlands of Tigray, Northern Ethiopia:implications for potential zoonoses

We studied associations between rodents and their arthropod ectoparasites in crop fields and household compounds in the highlands of Tigray,Northern Ethiopia.Ectoparasite infestation indices,such as percent infestation,mean abundance,prevalence and host preferences,were calculated for each taxon.In total,172 rodents from crop fields and 97 from household compounds were trapped.Rodent species and numbers trapped from the crop fields and household compounds were Mastomys awashensis(Lavrenchenko,Likhnova&Baskevich,1998)(88 and 44),Arvicanthis dembeensis(Ruppel,1842)(63 and 37)and Acomys sp.(21 and 16),respectively.A total of 558 insects and acarids(belonging to 11 taxa)were recovered from the rodents trapped in the crop fields,and 296 insects and acarid(belonging to 6 taxa)from the rodents trapped in the household compounds.Approximately 66%of the rodents trapped from the crop fields and 47%of those trapped from the household compounds were infested with ectoparasites.Laelaps sp.(64.9%)and Xenopsylla sp.(20.6%)comprised the highest proportion of the ectoparasites recovered in the crop fields,and the same ectoparasites,but in reverse order,comprised the highest proportions in the household compounds(Xenopsylla[50.3%]and Laelaps sp.[29%]).Our study revealed that crop fields and household compounds in the highlands share similar rodents and several ectoparasites.Furthermore,at least 1 of the rodent species and some of the ectoparasites identified in this study were reported to have posed medical and veterinary threats in other parts of Ethiopia and neighboring countries.

A survey of zoonotic diseases in trade cattle slaughtered at Tanga city abattoir:a cause of public health concern

Objective:To estimate the prevalence of hydatidosis,cysticercosis,tuberculosis,leptospirosis,brucellosis and toxoplasmosis in slaughtered bovine stock(aged≥3 years)at Tanga city abattoir,Tanzania.Methods:Prevalence estimation of the five zoonotic diseases was undertaken through an active abattoir and sero-survey was carried out in Tanga city,during the period of January 2002and March 2004.Serum samples collected from a sub-sample(n=51)of the slaughter stock were serologically screened for antibodies against brucellosis,leptospirosis and toxoplasmosis using Rose Bengal plate test,microscopic agglutination test(for 5 serovars of Leptospira interrogans)and Eiken latex agglutination test,respectively.The same animals were tested for tuberculosis using the single intradermal tuberculin test.Results:Post mortem examination of 12 444 slaughter cattle(10 790 short horn zebu and 1 654 graded)over a period of twenty two months,showed a prevalence of 1.56%(194)for hydatidosis,1.49%(185)for cysticercosis and 0.32%(40)for tuberculosis.In all three zoonoses,a statistically significant difference in infection rates was noted between the short horn zebu and graded breeds(P<0.05).The overall seroprevalences of animals with brucellosis,toxoplasmosis and leptospirosis antibodies were found to be 12%,12%and 51%,respectively.The most common leptospiral antibodies detected were those against antigens of serovars Leptospira hardjo(29%),Leptospira tarassovi(18%),Leptospira bataviae(4%)and Leptospira pomona(0%).With regard to tuberculosis,10%(n=5)of the animals tested were classified as non-specific reactors or inconclusive.Conclusions:The study findings suggest that brucellosis,toxoplasmosis and leptospirosis are prevalent in Tanga and provide definitive evidence of slaughtered stock exposure to these zoonotic agents with concurrent public health consequences.

Detection of Trypanosoma spp. in Bandicota indica from the Thai-Myanmar border area, Mae Sot District Tak Province, Thailand

Objective:To investigate the prevalence of trypanosome infection and their phylogeny in Bandicota indica rats from the cadmium-contaminated area of Mae Sot and the Myanmar border.Methods:Blood samples were taken from 100 animals,and parasite infection was examined by light microscopy observation and polymerase chain reaction(PCR)studies.Results:Trypanosoma spp.infection was found in 20%of the thin blood smear samples.PCR showed positive 623 bp DNA bands in 21 samples(21%).The sequencing analysis showed that all of the samples(100%)had the Trypanasoma lewisi 18 S ribosomal RNA gene.Phylogenetic analysis confirmed that these 16 isolates of Trypanosoma spp.were closely related to Trypanasoma lewisi.Conclusions:Molecular detection using PCR is as effective as conventional light microscopy analysis.This study confirms that trypanosomal infection in rodents is still high;therefore,fleas as their vectors need to be controlled in order to prevent transmission to humans.

Brazilian vaccinia virus strains show a classical orthopoxvirus infection course and cross-protection

【正】Objectives:The purpose of this work was to study the infection course and cross-protection in mice after intradermal injection of Vaccinia virus(VACV) strain Western Reserve and three Brazilian VACV strains: Aracatuba,Muriae and BeAn58058 isolated from cow,human and rodent,respectively.Methods:Balb/c mice were inoculated by footpad and back scarification and daily monitored regarding lesion development and weight loss.To check cross protection after intradermal VACV inoculation,mice were subsequendy infected with different VACV strains and monitored to check lesion development.Serum neutralization assays were performed to check for the presence of antibodies against Orthopoxvirus.Results:After VACV intradermal inoculation the lesion development pattern was similar in mice infected with the different virus strains.By using the footpad scarification model,cross-protection among VACV strains was observed.Moreover,neutralizing antibodies against Orthopoxvirus were detected in sera from mice infected with all VACV strains.Conclusion:Although it was not possible to observe virulence differences among VACV strains isolated from cow,rodent and human using the murine model,this inoculation route showed to be an appropriated model to study lesions development since it mimics natural infections by VACV in nature.

Evaluation of zoonotic potency of Escherichia coli O157:H7 through arbitrarily primed PCR methods

Objective: To evaluate the zoonotic potency of Escherichia coli O157:H7 through arbitrarily primed-PCR(AP-PCR) methods as one of the DNA fingerprinting methods.Methods: A total of 14 isolates consisted of 11 isolates originated from human feces with renal failure symptoms, 2 isolates originated from cattle feces, and 1 control isolate were used in this study. DNA of each isolate was extracted, and their pro files were studied by using AP-PCR method with M13 F and M13 R arbitrary primers.Results: The results founded that all of 14 isolates had similarity range from 54.6% to88.5%. Isolates KL-106(3) and KL-55(6) originated from humans showed the degree of similarity with isolates SM-25(1) and SM-7(1) originated from cattle as high as 85% and77%, respectively.Conclusions: The high degree of similarity between isolates originated from cattle and human indicated the high potency of zoonoses. The results also concluded AP-PCR method as a brie fly fingerprinting method in order to trace the epidemiological of E. coli O157:H7.

Virome in healthy pangolins reveals compatibility with multiple potentially zoonotic viruses

Previous studies have identified multiple viruses in dead or severely diseased pangolins,but descriptions of the virome in healthy pangolins are lacking.This poses a greater risk of cross-species transmission due to poor preventive awareness and frequent interactions with breeders.In this study,we investigated the viral composition of 34 pangolins with no signs of disease at the time of sampling and characterized a large number of arthropodassociated viruses belonging to 11 families and vertebrate viruses belonging to eight families,including those with pathogenic potential in humans and animals.Several important vertebrate viruses were identified in the pangolins,including parvovirus,pestivirus,and picobirnavirus.The picobirnavirus was clustered with human and grey teal picobirnaviruses.Viruses with cross-species transmission ability were also identified,including circovirus,rotavirus,and astrovirus.Our study revealed that pangolins are frequently exposed to arthropod-associated viruses in the wild and can carry many vertebrate viruses under natural conditions.This study provides important insights into the virome of pangolins,underscoring the importance of monitoring potential pathogens in healthy pangolins to prevent outbreaks of infectious diseases in domesticated animals and humans.

Monkeypox awareness,knowledge,and attitude among undergraduate preclinical and clinical students at a Malaysian dental school:An emerging outbreak during the COVID-19 era

Objective:To evaluate the awareness,knowledge,and attitude on monkeypox viral infection among preclinical and clinical dental students in Malaysia.Methods:A cross-sectional study was conducted among 229 preclinical and clinical dental students via an online self-reported questionnaire.The questionnaire included 3 items on awareness,15 items on knowledge,9 items on attitude and 2 open-ended questions.Data were presented as frequencies and percentages.Chi-square test was used to compare knowledge and awareness scores between preclinical and clinical dental students and content analysis was performed for open-ended responses.Results:Preclinical and clinical dental students were aware of the existence of monkeypox(89.5%and 94.4%,respectively),that the disease emerged in non-endemic countries(81.0%and 87.1%,respectively)and that it was declared a public health emergency of international concern by the World Health Organization(73.3%and 79.0%,respectively).Clinical dental students’overall knowledge level was significantly higher than preclinical dental students(P=0.014).Both preclinical(95.2%)and clinical(96.8%)dental students demonstrated positive attitudes toward monkeypox with no significant difference(P=0.736)noted between them.Three themes emerged from the open-ended questions:(1)reimplementation of nationwide lockdown,(2)impact on the economy and health,and(3)disruption to the educational system.Students also anticipated their face-to-face learning to be reduced should there be a new outbreak.Conclusions:Both preclinical and clinical dental students showed comparable awareness and attitudes,while the latter demonstrated greater satisfactory knowledge toward the re-emergence of monkeypox during the COVID-19 pandemic.Nonetheless,efforts to improve dental students’understanding of this alarming outbreak are required,to safeguard their health and minimise transmission.

China's great wall, Israel's Bar Lev Line, and passive infectious disease surveillance

Emerging infectious diseases are some of modern society's greatest threats. Like some great construction efforts designed to protect mankind, current public health measures against these emerging pathogens have not always been successful. This paper highlights the importance of embracing new interdisciplinary approaches towards emerging pathogen threats. One such approach, termed One Health, is quickly being embraced by professional organizations and public health institutions across the world as a way forward. This paper briefly discusses the above problems and preliminary steps taken by Chinese academic institutions to embrace the One Health approach.

New Record of Civets at Bharatpur, Chitwan and a Review of the Species Diversity in Nepal

Civets are alluring nocturnal carnivores having variant external features with different coat colors, stripes and spots, carpal and metatarsal pads, closed or open peri-anal scent glands in both sexes which have great taxonomic value and make these animals acclimatize in a wide range of geographical landscapes from hilly areas to patchy gardens and thin forests of the low land (Terai) located in or near the human settlement areas. The range of Head Body Length (HBL) and Tail Length (TL) in Paradoxurus spp. and Viverricula spp. distinguishes civets from felids. The study of civets was carried out by direct observation and videos and/or photographs were taken in the sighted places with the record of geological coordinates as evidence. For the record of civets, four wards (i.e. 7, 10, 11 and 12) were selected from Bharatpur Metropolitan City by lottery methods from the purposively selected 15 wards out of 29. These selected wards were visited randomly once or upon call in a month riding on a motorbike at the speed of 10 to 20 kilometer per hour in average speed and was crossed 2400 kilometers during four years beginning from January, 2016 to December, 2019. As a result, 11 civets of three Species, six Subspecies and two genera (i.e. Paradoxurus spp. and Viverricula spp.) were recorded. Among these animals, four subspecies were from Paradoxurinae and two were from Viverrinae subfamilies. Likewise, Paradoxurus jerdoni caniscus were reported, 9.09% (n = 1);Paradoxurus hermaphroditus minor, 9.09% (n = 1);Paradoxurus hermaphtoditus pallasii, 54.55% (n = 6);Paradoxurus hermaphroditus hermaphroditus, 9.09% (n = 1); Viverricula indica baptistae, 9.09% (n = 1);and Viverricula indica mayori, 9.09% (n = 1). Conclusively, the first records of the civet Species and Subspecies from thin gardens of fruiting trees and human houses or settlement areas in the city of Bharatpur, Chitwan, have created a great field to explore ecology and population status. However, human-civet conflicts have been created by the potential harm to poultry and pets as well as possible reservoir hosts of parasitic zoonoses and Covid-19 Viruses. Consequently, the population of civets is declining in an alarming rate due to the threats of vehicle and electric accidents, snaring and random killing by the people.

First Evidence of Hantavirus in Central Iran as an Emerging Viral Disease

Hantavirus is a zoonosis transmitted from rodents to humans. Asymptomatic infected rodents can secrete hantaviruses in the urine, feces, and saliva. The main route of infection transmission to human is aerosols contaminated with the virus. This study was designed to evaluate the serological and molecular prevalence of hantavirus as an emerging zoonoses disease among street sweepers in Isfahan province, central Iran. Serum samples from 200 street sweepers in healthy condition and those with recent renal failure were tested by ELISA (IgM and IgG). Molecular analysis was subsequently applied for IgM positive cases. From these samples, 9 (4.5%) were positive, of which 2 (22.22%) were positive for both IgM and RT-PCR, while 7 (77.77%) were positive for IgG. The mean age and work experience of the positive cases were 39.7 and 11.5 respectively. According to our observations, all positive cases reported prevalence of rodents in their work place. The logistic regression test showed that the age and work experience were not risk factors for being positive, but prevalence of rodents in work place was a risk factor for being positive, when compared with negative cases. This is the first comprehensive study on the prevalence of hantavirus with positive results coming from Iranian population, which can raise the public awareness for the hantavirus infections as a public health threat.

Weil’s Disease (Fulminating Leptospirosis) Complicating as Acute Respiratory Distress Syndrome

Leptospiroisis presents with a wide range of clinical symptoms, ranging from mild disease symptoms to life threatening complications. The clinical features and routine laboratory findings are not specific, and therefore a high index of suspicion must be maintained for the diagnosis. We documented a case of a patient, who presented with high grade fever, diarrhea, vomiting, had icterus on examination. Initial laboratory investigations revealed low platelet count, along with raised liver enzymes. IgM leptospirosis came positive and patients received broad spectrum antimicrobials and supportive fluid therapy. During admission, patient developed sudden onset breathlessness, which was diagnosed as acute respiratory distress syndrome after doing immediate arterial blood gases. The patient received noninvasive ventilation with positive airway pressure, from which the patient eventually recovered. Most of the cases of leptospirosis are uneventful with complete recovery. However, a minority of these cases may end with life threatening complications. A vaccine for human use is not available in most countries. Therefore, the prevention involves reducing exposure, either by avoiding situations that pose a risk of transmission or using protective clothing.

Bacteriome in Ticks Collected from Domestic Livestock in Kenya

Background: Metagenomics approaches are increasingly being utilized as “dipstick” for microbial carriage. In this study, 16S rRNA metagenomics was used to probe for microbial community that resides in the ticks, those they pick from the environment, wildlife and livestock and to identify potential tick borne zoonoses. Methods: Tick DNA from 463 tick pools collected from domestic animals between 2007 and 2008 were amplified with primers that target the 16S rRNA V3-V4 domain and then sequenced on Illumina Miseq platform using 300 cycles version 3 kits. Ticks were pooled according to species and animal from which they were collected. A non-target control was used to track laboratory contaminants. Sequence data were analyzed using Mothur v1.3 pipeline and R v3.3.1 software and taxonomy determined using SILVA rRNA database. Shannon diversity index was used to compute bacterial diversity in each tick species before computing the means. Results: A total of 645 bacteria genera grouped into 27 phyla were identified. Four phyla contributed 97.4% of the 36,973,934 total sequences. Proteobacteria contributed 61.2% of these sequences that tarried to 33.8% genera, compared to 15.9% (23.4% genera) for Firmicutes, 15.6% (20% genera) for Actinobacteria and 4.7% (11.6% genera) for Bacteroidetes. The remaining 23 phyla only contributed 2.6% of the sequence reads (11.2% genera). Amongst the 645 genera, three groups were discernible, with the biggest group comprised commensals/symbionts that contributed 93.6% of the genera, but their individual sequence contribution was very low. Group two comprised genera that are known to contain pathogenic species, with Coxiella contributing 15,445,204 (41.8%) sequences, Corynebacterium (13.6%), Acinetobacter (4.3%), Staphylococcus (3.9%), Bacillus (2.7%) and Porphyromonas (1.6%), Ralstonia (1.5%), Streptococcus (1.3%), Moraxella (1.3%), amongst others. Group three comprised genera known to contain tick borne zoonotic pathogens (TBZ): Rickettsiae, Anaplasma, Francisella, Ehrlichia, Bartonella and Borrelia. Individually the TBZ contributed Amblyomma variegatum carried the least diverse bacteria (mean Shannon diversity index of 2.69 ± 0.92) compared to 3.79 ± 1.10 for A. gemma, 3.71 ± 1.32 for A. hebraeum, 4.15 ± 1.08 for other Amblyomma spp, 3.79 ± 1.37 for Hyalomma truncatum, 3.67 ± 1.38 for other Hyalomma spp, 3.86 ± 1.27 for Rhipicephalus annulatus, 3.56 ± 1.21 for Rh. appendiculatus, and 3.65 ± 1.30 for Rh. Pulchellus, but the difference was not significant (p = 0.443). Conclusion: This study illustrates the utility of 16S rRNA metagenomics in revealing the complexity of bacteria communities that reside and/or transit through the tick having been picked from the environment, livestock and/or wild animals, some with potential to cause zoonoses.